FRANKFURT--Allianz Global Investors, one of two units in Allianz SE's (ALV.XE) asset management business, said Tuesday it plans to bundle all European units in one operating entity by the end of 2013 or early 2014 as it reorganizes its European business.

The move aims to make the business more efficient, streamline the product range and cut costs, including reducing staffing levels, James Dilworth, Chief Executive of Allianz Global Investors Europe, said.

Allianz Global Investors became one of the two pillars in Allianz's asset management operations, when Allianz restructured the business in September 2011 with the goal of making two brands--Allianz Global Investors and Pimco--separate entities and move away from the family of boutiques model.

It plans to set up three centers in Europe in Frankfurt, London and Paris, similar to the unit's setup in the U.S. and Asia, with Frankfurt likely to be the European headquarters.

Mr. Dilworth said he couldn't give an estimate of total cost savings expected from bundling the units and the unit hopes to reduce total costs in Europe by 4% by cutting staff, confirming a German media report earlier Tuesday. He said the Allianz unit is in talks with European labor representatives over the planned reduction.

Allianz Global Investors reported a cost-income ratio of about 75% for the first quarter, which is "several basis points too high," but should be lowered by both cutting costs and increasing revenues in Europe, the U.S. and Asia, Mr. Dilworth said.

The restructuring, which will start in Germany in the fourth quarter, also aims to strengthen the brand Allianz Global Investors to compete with local rivals, including AGF in France, RAS in Italy and RCM in the U.K., and to boost retail investors' net inflows, Mr. Dilworth said.

Write to Ulrike Dauer at ulrike.dauer@dowjones.com